well if its a 500 it will more than pull all them things and then some just fine
E shift just means it has an electric shift to change gears rather than doing it with a lever.
Some folks love it, some prefer a manual shift , and some prefer a fully automatic ATV all together
Having gears over an auto makes pulling trailers to me a LOT easier on the atv and you, as it keeps speeds and power where you want it without it trying to shift on its own, as an auto would want to do.
when buying used, its always a gamble, as many used atv's have seen hard days and poor maintenance, and its very hard to tell by looking, all the more so if you don't know much about them
as sadly most sellers do theer best to hide abuse, with new paint plastics orjust a good cleaning
I highly recommend asking around for some that knows more about atv's to go with you to look at any potential
typical things to look out for IMO
is Snorkels and aggressive Large mud tires, that tends to mean the old owner liked to ride in either deep water or mud, and that substantially increases the odds they sunk the motor in water, its a VERY common thing in today's world of ATV riders
next common issues will be wheel bearings that are worn, ask to inspect Air filter(easy to do) and look to see how clean or dirty is it, a good owner will clean it often, so if its filthy, that says they were slow on taking care of basic's to me!
look for bent wheels, about the beads, it happens, but very aggressive trail riding can have a lot more dents, and says the owner didn't just Sunday drive it LOL
it should start almost instantly when the starter button is pushed too, any SLOW cranking to get it up and going, says??
which brings me to, IF when you go to look at it, the motor is HOT< that can also mean it has issues on cold starts or smokes(sign of a motor issue) and some guys run them to get them hot to stop burning oil before you come.
SO< watch out for this, and also look for smoke out the exhaust
NOW< not trying to scare you, there are some honest folks out there, but there sadly FAR and few in todays world I fear
hate to see anyone get burned
Lots of good folk's on this site, so if you say where your from, maybe one from here can help you find a good atv?
BUT a Honda rancher, Foreman, or Rubicon, Rincon will ALL do what your looking for in the 400+ cc range!